An Overview of Criminal Justice System of China and Comparison with Iran by Emphasizing Fair Trial in Primary Investigation Stage

China has a rich history and culture but the legal system of the country is quite new and young. Many who got accustomed to their legal system, court decisions, and regulations, are wondering why China as a great nation in terms of area and population didn't formulate its current Criminal Procedure Code until 1979. In this country, the trend toward a socialist free-market economy, concerns related to following human rights, and forging investments have resulted in the review and amendment of Criminal Procedure Code in 1996, 2012, and 2018. Several outcomes of the new code are as follows: approval of presumption of innocence and specifying several of its effects, e.g., the necessity of interpreting in dubio pro reo (in doubt, for the accused), forbidding the act of compelled self-incrimination, and prescribing the lawyer's intervention with several restraints in the primary investigation stage.Iran Criminal Procedure Code (1392) is also moving away from the inspection system in the primary investigation stage toward adversarial criminal procedure obliging the criminal procedure process actors to follow fair trial principles and respect the rights of the accused to defend himself/herself. Although this Code has considered several suitable sanctions for violating the rights of the accused, they don't seem enough. Recently, the two countries have involved in mutual partnerships in different areas based on mutual benefits but there has been no research carried out to compare the subjects of criminal law in both countries. Therefore, it seems fit to carry out the current research on this subject.